Process of hardening copper.



UNITED STATES PATENT OFFICE.

HENRY VONPHUL DRAPER, OF SPRINGFIELD, MISSOURI, 'ASS IGNOR OFONE-HAIiF-TO GEORGE A. HANCOCK, OF SPRINGFIELD, MISSOURI.

PROCESS OF HARDENING COPPER.

Application filed June 10,

To all whom itmay concern."

Be it' known that I, HENRY VONPHUL DRAPER, a citizen of the UnitedStates, resid-- ing at Springfield, in the county of Greene and State ofMissouri, have invented new and useful Improvements in Processes ofHarden ing Copper, of which the following is a specification.

The invention relates to a process for harable, retort or furnace, andthe ingredients named above are added thereto. I have found in practicethat the following proportions will yield the best results, though I donot wish to limit myself exactly thereto. For twenty pounds of co per Iuse one pound of ulvcrized alum an four ounces of .arsenic. I have alsofound that better results areobtained by mixing the pulverized alum andarsenic thoroughly together before introducing them into the retort.

The melted copper isslightly chilled .on the addition of the ingredientsnoted, but a thorough commingling is attained by subjecting the materialto thefurther action of the heat until the visual presence of the in-Specification of Letters Patent.

Patented Aug. 18, 1908.

1905. Serial No. 2 4,729.

.gredients has been removed and the mass presents a uniform appearance.After this ough agitation or stirring, and is then ready to be pouredinto the molds. The resultant metal is of great density, toughness anduse in those situations requiring a metal of this nature. Anotherdecided advantage resulting from my process is that the metal maybere-melted as often as desired without losing the characteristicsimparted to it as the essential result of the process. .Having thusdescribed the invention, what I claim as new, is

1. The process of hardening copper which consists in mixing with themolten metal alum and arsenic, subjecting the mixture to the furtheraction of heat and thoroughly agitating the mixture before cooling.

- 2. The herein described process of hardenpulverized alum and arsenic,and adding the mixture to copper while in a molten state.

In testimony whereof, I allix my signature in presence of two witnesses.

HENRY VONPHUL DRAPER.

Witnesses: R. E. WA'rsoN H. P. JOHN.

combining the mass is subjected to a thor-- ing copper consisting inthoroughly mixing- -hardness, and is particularly serviceable for

